Obesity has reached epidemic proportions in the US. One approach to stemming this epidemic is expanding the science about critical periods of obesity development such as the period surrounding childbearing. Not only is childbearing a critical period for weight gain and obesity development for US women, it is also a key turning point that may have negative effects on health behaviors, such as exercise; mood; and body image. These multiple dimensions of well-being are integrated in a preliminary model of "thriving" in postpartum. Thriving as a framework for studying weight management in postpartum integrates weight with (1) promoting healthy lifestyles; (2) managing psychosocial distress; and (3) enhancing body image satisfaction. The thriving model also includes both static (such as ethnicity) and dynamic factors (such as lactation). This study will validate with low income African American, Hispanic, and White women during the first year after childbirth a thriving-based model of postpartal weight management. Study aims include (1) comparing dimensions of thriving in African American, Hispanic, and White women; (2) examining relationships between weight status and factors influencing thriving, especially those mediated by ethnicity; (3) validating relationships between measured weight status and psychosocial variables; (4) exploring relationships between measured weight status and macro- and micronutrients in the diet; and (5) formulating a model for weight management intervention during postpartum for women at risk of continued overweight. A sample of 556 low income women (33.3 percent white, 33.3 percent black, and 33.3 percent Hispanic) will be recruited into a prospective, longitudinal design with assessments at shortly after birth in the hospital; 6 weeks, and 3,6, and 12 months postpartum. At these time points, observations will be made on body mass index based on measured weights, dietary intake of macro- and micro-nutrients, physical activity, food habits, self-care practices, body image, weight-related distress, and depressive symptoms. Study outcomes include formulation of a model for weight management intervention after childbirth for overweight women which takes into account influencing factors, and patterns of postpartal weight loss for African American, Hispanic and White women.